A new method of suboptimal control for batch and fed-batch fermentation processes is proposed. It combines the properties of program and adaptive control methods. The main idea of the method is to divide the controlled fermentation processes into classes using the integral characteristic of their individual properties-the peculiarity index(PI). It is assumed that any process that belongs to a class is identical to the class’ standard process (CSP). The optimal control programs for the CSP are derived off-line. The value of PI for the current process is determined on-line, and the control program that is used is the optimal one for the corresponding CSP. Industrial scale lysine fermentation processes are taken as an example. It is shown that the efficiency of the method is close to the efficiency of adaptive control, but that it is much simpler and its performance characteristics are better.